Technological scheme for the alkaline activation of lignite coals in the Far Eastern Region

The article shows the relevance of the theory and practice of deep coal processing. The increasing relevance is based on modern trends in the development of the global coal industry and forecasts regarding the decrease in demand for coal in the energy sector due to the introduction of alternative energy sources. The Russian Federation has the richest raw material base of coals, including lignite. Due to the low degree of metamorphism, lignite’s are unique in their properties and are very promising as a raw material for the production of sorbents for the treatment of industrial, municipal and industrial wastewater. The aim of the study is to develop a process flow chart for alkaline activation of lignite coals in the Far Eastern region to obtain high-quality sorbents for adsorption from the liquid phase. The laboratory study was conducted on lignite coals from four deposits in the Far Eastern region (Kharanorskoye, Kangalasskoye, Kirovskoye, Okino-Klyuchevskoye deposits). General scientific and empirical methods were used: analysis and generalization of scientific literature on the research problem, experiment, analysis, comparison and mathematical processing of the obtained experimental data. A study was conducted of various options for carrying out three stages of the process of obtaining sorbents (preparation of lignite coal for activation, alkaline activation and final processing). Analysis of the obtained data on the sorption properties of the obtained samples made it possible to determine the optimal parameters and sequence of operations in the process of alkaline activation of lignite coals. A process flow chart for alkaline activation of lignite coals with potassium hydroxide has been developed, consisting of 14 operations, including thermal leaching and mechanical activation. Carrying out the process of alkaline activation of lignite according to this technological scheme allows obtaining sorbents with high adsorption activity for iodine (more than 90 %). The results of the research allow us to speak about the technological feasibility, high efficiency and prospects of processing lignite coals from deposits in the Far Eastern into sorbents.